(Table T1) Element concentrations and Strontium and Neodymium isotopes of ODP Hole 191-1179D basalts

Sr and Nd isotopic compositions of 19 basalts from Hole 1179D, Leg 191 were analyzed to determine ridge and plume interaction. 87Sr/86Sr and 143Nd/144Nd ratios of the basalts ranged from 0.7029 to 0.7040 and from 0.5131 to 0.5132 (epsilon Nd0 = 9.3 ~ 10.8), respectively. Calculated initial isotopic compositions at 129 Ma, the age of magnetic Anomaly M8, are 87Sr/86Sri = 0.7026 ~ 0.7033 and epsilon NdT = 9.2 ~ 10.6. The initial Sr isotope ratio is higher than that of normal mid-ocean-ridge basalts (MORBs) from the East Pacific Rise and Mesozoic MORBs. They are similar to those of the Shatsky Rise, suggesting a plume component was involved in the formation.